Rice Univ. scientists have invented a novel cathode that may make cheap, flexible dye-sensitized solar cells practical. The Rice laboratory of materials scientist Jun Lou created the new cathode, one of the two electrodes in batteries, from nanotubes that are seamlessly bonded to graphene and replaces the expensive and brittle platinum-based materials often used in earlier versions.
After graphene was first produced in the laboratory in 2004, thousands of laboratories began...
Univ. of Utah engineers have developed a new type of carbon nanotube material for handheld...
Researchers in the U.K. have found a new way to make nanostructured carbon using the waste product sawdust. By cooking sawdust with a thin coating of iron at 700 C, they have discovered that they can create carbon with a structure made up of many tiny tubes. These tubes are one thousand times smaller than an average human hair.
Univ. of Oregon chemists have devised a way to see the internal structures of electronic waves trapped in carbon nanotubes by external electrostatic charges. Their atomic scale observations provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices.
Researchers in Australia have discovered that nano-sized fragments of graphene have the ability to speed up the rate of chemical reactions. The finding is significant, say researchers, because it suggested that graphene might have potential applications in catalyzing chemical reactions of industrial importance.
Researchers at the Univ. of Pennsylvania and The Children's Hospital of Philadelphia have used graphene to fabricate a new type of microelectrode that solves a major problem for investigators looking to understand the intricate circuitry of the brain. The see-through, one-atom-thick electrodes can obtain both high-resolution optical images and electrophysiological data for the first time.
Personal electronics such as cell phones and laptops could get a boost from some of the lightest materials in the world. Lawrence Livermore National Laboratory researchers have turned to graphene aerogel for enhanced electrical energy storage that eventually could be used to smooth out power fluctuations in the energy grid.
Graphene’s exotic properties can be tailored by cutting large sheets down to ribbons of specific lengths and edge configurations. But this “top-down” fabrication approach is not yet practical, because current lithographic techniques always produce defects. Now, scientists from the U.S. and Japan have discovered a new “bottom-up” self-assembly method for producing defect-free graphene nanoribbons with periodic zigzag-edge regions.
Researchers in Japan have developed a new yet simple technique called "diffusion driven layer-by-layer assembly" to construct graphene into porous 3-D structures for applications in devices such as batteries and supercapacitors. The new method borrowed a principle from polymer chemistry, known as interfacial complexation, to allow graphene oxide to form a stable composite layer with an oppositely charged polymer.
Researchers at Japan’s National Institute of Advanced Industrial Science and Technology have synthesized an atomic chain in which two elements, cesium and iodine, are aligned alternately inside a carbon nanotube. Analyzed using electron microscopy and spectroscopy, the invention could shed light on the adsorption mechanisms of radioactive elements.
When trying to design a mechanical system to last as long as possible, scientists and engineers have to find ways of overcoming friction. While researchers have found many materials that help to reduce friction, conventional lubricants often have chemical limitations. A recent analysis at Argonne National Laboratory has identified the properties of a newer, wear-resistant substance that works in a broader range of environments.
When Illinois researchers set out to investigate a method to control how DNA moves through a tiny sequencing device, they didn’t know they were about to witness a display of molecular gymnastics. Fast, accurate and affordable DNA sequencing is the first step toward personalized medicine.
A Duke Univ. team has found that nanoparticles called single-walled carbon nanotubes accumulate quickly in the bottom sediments of an experimental wetland setting, an action they say could indirectly damage the aquatic food chain. According to the research, the risk to humans ingesting the particles through drinking water is slight, but aquatic food chains might be harmed by molecules "piggybacking" on the carbon nanoparticles.
Graphene quantum dots created at Rice Univ. grab onto graphene platelets like barnacles attach themselves to the hull of a boat. But these dots enhance the properties of the mothership, making them better than platinum catalysts for certain reactions within fuel cells.
In experiments using graphene, researchers in Switzerland have been able to demonstrate a phenomenon predicted by a Russian physicist more than 50 years ago. The observation of the Lifshitz transition, which describes a change in topology, depended on the creation of a double-layer graphene sample of unprecedented quality.
A Rice Univ. team led by bioengineer Jeffrey Jacot and chemical engineer and chemist Matteo Pasquali have created new pediatric heart-defect patches infused with conductive single-walled carbon nanotubes that allow electrical signals to pass unhindered. The nanotubes overcome a limitation of current patches in which pore walls hinder the transfer of electrical signals between cardiomyocytes, the heart muscle’s beating cells.
Researchers have discovered a way to create a highly sensitive chemical sensor based on the crystalline flaws in graphene sheets. The imperfections have unique electronic properties that the researchers were able to exploit to increase sensitivity to absorbed gas molecules by 300 times.
A new, ultrasensitive biosensor made from graphene has been used to detect molecules that indicate an increased risk of developing cancer. The biosensor has been shown to be more than five times more sensitive than bioassay tests currently in use, and was able to provide results in a matter of minutes, opening up the possibility of a rapid, point-of-care diagnostic tool for patients.
Researchers at Argonne National Laboratory have created a small scale “hydrogen generator” that uses light and a 2-D graphene platform to boost production of the hard-to-make element. The research also unveiled a previously unknown property of graphene. The 2-D chain of carbon atoms not only gives and receives electrons, but can also transfer them into another substance.
Glenn Johnson, CEO of BlueVine Graphene Industries Inc., said many of the methodologies being utilized to produce graphene today are not easily scalable and require numerous post-processing steps to use it in functional applications. He said his company has developed a way to scale graphene production using a roll-to-roll chemical vapor deposition process.
While freestanding graphene offers promise as a replacement for silicon and other materials in microprocessors and next-generation energy devices, much remains unknown about its mechanical and thermal properties. An international team of physicists, led by a research group at the Univ. of Arkansas, has recently discovered that heating can be used to control the curvature of ripples in freestanding graphene.
Many a great idea springs from talks over a cup of coffee. But it’s rare and wonderful when a revelation comes from the cup itself. Rice Univ. theoretical physicist Boris Yakobson, acting upon sudden inspiration at a meeting last year, obtained a couple of spare coffee cups from a server and a pair of scissors and proceeded to lay out—science fair-style—an idea that could have far-reaching implications for the nanotechnology industry.
Rice Univ. scientists who created a deicing film for radar domes have now refined the technology to work as a transparent coating for glass. The new work by Rice chemist James Tour and his colleagues could keep glass surfaces from windshields to skyscrapers free of ice and fog while retaining their transparency to radio frequencies (RF).
A new method for controllably constructing precise inter-nanotube junctions and structures in carbon nanotube (CNT) arrays, Northeastern Univ. researchers say, is facile and easily scalable. It will allow them to tailor the physical properties of nanotube networks for use in applications ranging from electronic devices to CNT-reinforced composite materials found in everything from cars to sports equipment.
In recent years, it has become possible to see directly individual atoms using electron microscopy, especially in graphene. Using electron microscopy and computer simulations, an international team has recently shown how an electron beam can move silicon atoms through the graphene lattice without causing damage.
The very idea of fibers made of carbon nanotubes is neat, but Rice Univ. scientists are making them neat—literally. The single-walled carbon nanotubes in new fibers created at Rice line up like a fistful of uncooked spaghetti through a process designed by chemist Angel Martí and his colleagues.
When moving through a conductive material in an electric field, electrons tend to follow the path of least resistance—which runs in the direction of that field. But now physicists have found an unexpectedly different behavior under very specialized conditions—one that might lead to new types of transistors and electronic circuits that could prove highly energy efficient.
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